1. Field of the Invention
The present disclosure relates to a detecting method. More particularly, the present disclosure relates to a method of detecting a lubrication status between a deck and a belt of a treadmill.
2. Description of the Related Art
Currently, a typical electric treadmill has a platform which comprises a frame, a rectangular deck sustained on the frame, two parallel rollers pivotally mounted on the frame and disposed at the front end and the rear end of the deck, an endless belt mounted around the front roller and the rear roller and across a top and a bottom of the deck, and a motor for driving the front roller. In a normal driving mode, when the belt is driven by the roller to rotate forwardly, the portion of the belt on the top of the deck is circularly rotated from the front to the rear, so that an exerciser could walk or run on the belt in place. Namely, when the exerciser steps on the belt, the underneath deck would support the weight of the exerciser; meanwhile, the belt would also sustain the feet of the exercise flatting on the top of the deck to slide backward until the feet of the exercise raises to step forward again.
In the above configuration, the top surface of the deck and the inner surface of the belt are generally applied the lubrication action, e.g. waxing or oiling so as to have the stepping portion of the belt be able to slide over the deck smoothly. However, since the interface between the deck and the belt may gradually appear chips, dust, etc. Besides, the waxing layer and the lubricating oil at the top surface of the deck and the inner surface of the belt would also gradually wear and disappear. In other words, the lubrication status between the belt and the deck would become progressively worse over time. Therefore, the treadmill owner or treadmill maintenance personnel need to clean the top surface of the deck and the inner surface of the belt regularly, and/or add the lubricating oil or the like to the top surface of the deck and the inner surface of the belt. Otherwise, when the coefficient of friction between the belt and the deck is too large, the power consumption of the treadmill will increase, the motor may overheat easily, the life time of the belt and the deck will be shortened, more importantly, the running or walking movement of exerciser will become not smooth, and the belt may even get stuck to cause danger. In contrary, if the lubrication status between the belt and the deck is still normal, but inexperienced maintenance personnel still add lubricating oil to the interface of the deck and the belt, it may cause the inner surface of the belt over lubrication so that the slip phenomenon between the belt and the roller may occur easily, and not only reduces the transmission efficiency, but also affects the exercising of the exerciser so that it is dangerous.
Therefore, to correctly determine the lubrication status of the belt and the deck and to clean and lubricate appropriately, are maintenance priorities of ensuring the normal operation of the treadmill. However, because the abrasion and the consumption rate of the lubricating substance on the top surface of the deck and the inner surface of the belt will be varied from the actually running mileage for user use, exercising modes such as speed, grade, the user's weight, seasons and climate, the composition of the lubricating substance, etc., to arrange every few months or a fixed number of cumulative hours to perform one operation of cleaning and lubricating, may not be the most appropriate time for maintenance. Certainly, if the user doesn't maintain until the movement of the belt is not smooth, it is usually too late since the inner surface of the belt and the top surface of the deck may wear seriously and the belt must be replaced, renewed or the deck must be turned for being used normally.
In order to accurately detect the lubrication status of the belt and the deck, the treadmill maintenance personnel may use a professional apparatus through a set of manual procedure to calculate the coefficient of friction. However, the professional apparatus is very expansive, and the calculation result is influenced by many operating conditions such that the accuracy needs to rely on the detecting technique of the personnel.
One existing technique is achieved by mans of monitoring the current consumption of the treadmill or motor to simply determine the lubrication status between the belt and the deck. For example, the product on the market is called “Treadmill Saver®”, which is connected between an indoor power socket and a power input port of the tested treadmill. The device not only transfers power to the treadmill, but also continuously monitors the current consumption of the whole treadmill. According to the high/low level of the average current consumption, the device will show different lights to notice the corresponding messages. Specifically, from lower power consumption to higher power consumption, the device will represent green light for “normal use/routine maintenance”, yellow light for “should be checked” and red light for “should repair”; the principle is, since the treadmill power consumption is mainly on the use of the motor to drive the belt, in theory if other variables is ignored, when the friction force between the belt and the deck becomes larger/smaller, the current consumption of the motor (corresponding to the output torque of the motor) will be higher/lower. Therefore, when the average current consumption of the treadmill in a period (e.g. the actual use of 10 hours) exceeds one preset warning value, it usually presents that the friction coefficient between the belt and the deck is too high and the treadmill should be maintained or repaired. Base on the same principle, the circuit system of the treadmill may be designed to monitor the current consumption of the motor directly, and to display the relevant information on the console of the treadmill. However, simply base on the average current consumption of the treadmill or the motor in the period to determine the lubrication status between the belt and the deck, it would ignore a number of factors that may affect the current level within that period, e.g. the weight of the exerciser, the speed of the belt, the grade of the platform, other power consumption of the treadmill. Thus, the accuracy and the reliability of the judgment result are not enough to correctly calculate the coefficient of friction between the belt and the deck.
According to the basic physics formula, the friction force of two contacting objects is equal to the relative force of the two objects perpendicular to the friction plane multiplied by the coefficient of friction. Applying the basic physics formula to the treadmill, when someone steps on the level platform and the belt is driven by the motor to slide over the top surface of the deck, the friction force between the belt and the deck is equal to the gravity force of the user multiplied by the friction coefficient between the belt and the deck. Thus, if knowing the output torque from the motor driving the belt (corresponding with the friction force) and the user weight (corresponding to said gravity force), in combination with other data (e.g. motor torque and drive ratio as no load is on the belt), the coefficient of friction between the belt and the deck might be appropriately calculated in theory. Namely, depending on the requirement of detecting the lubrication status between the belt and the deck, a set of detecting method may be designed, e.g. having the treadmill indicate an inspector to walk slowly on the belt at a low speed and measuring the motor torque or motor current during the procedure, and requiring the inspector to enter the weight value so as to calculate the coefficient of friction. However, most people are just roughly aware of their weight; besides, the daily body weight or total weight may be changed. Therefore, in the aforementioned methods, the difference between the weight entered by the inspector and the actual load on the belt will make the calculation result appear an error to influence the measuring accuracy and reliability. Of course, the inspector may use additional body weight meter to confirm the actual weight at first, but it will make the detecting procedure bothersome and incoherent; moreover, the body weight meter may be not accurate and available.
The present invention has arisen to mitigate and/or obviate the disadvantages of the conventional method. Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.